Where did the term "cup of joe" come from?

Today, the phrase "cup of joe" is just another way of saying "cup of coffee." In fact, there is even a coffee shop called Cup o' Joe. The phrase first appeared in print around 1930 and has since popularized. Though the exact origin of the phrase is unknown, there are three common theories that purport to have the answer. The first theory suggests that "cup of joe" is a byproduct of the 1860 song "Old Black Joe" by Stephen Foster. Given that the song fails to mention coffee and that the phrase "cup of joe" did not appear in print until 70 years later, this theory is likely not true.

The second theory holds that the phrase appeared as a result of the 1914 ban of officers' wine messes on U.S. naval ships imposed by admiral Josephus "Joe" Daniels. Since wine messes were no longer available on naval ships, officers would turn to coffee as a substitute. Accordingly, the theory holds, coffee became known as '"joe" after the man who, though indirectly, popularized it. This theory faces similar problems as the first: the ban on officer wine messes occurred prior to 1930 and, more importantly, the 1914 ban only eliminated wine messes for officers, having little effect on the coffee consumption of non-officer seamen who, since 1862, had faced a ban of alcohol on naval ships.

The third and most tenable theory holds that "joe" is derived from "java" or "jamoke," two common substitutes for "coffee" around 1930. The word "jamoke"was already a combination of java and mocha, so why not shorten it to "joe"?

Why are there colored dots on soda cans?

The colored dots found on aluminum soda cans near the nutrition information consist of all of the colors used in the can design. Of course, these colors vary depending on the design of the can. During manufacturing, a number of different machines apply color to each can; usually, each machine uses only one color. If a can makes it through production and its red dot, for example, is faded or absent, then laborers will be able to trace the problem to the single machine applying red color, without shutting down all of the machines to resolve the problem.

Why do some locomotives run backward?

Trains carrying large loads are usually pulled by two or three locomotives, collectively called a locomotive consist. Usually, the first locomotive is facing forward and the other locomotives are facing backward. This seemingly odd phenomenon is actually a common and convenient practice in the railroad industry. The leading locomotive faces forward to allow the conductor to see the path ahead and follow various signals. The second (and sometimes third) locomotive usually faces backward for the sake of convenience. Modern locomotives are able to run both "forward" and "backward" without compromising efficiency. That being said, by positioning a second locomotive backward behind a leading locomotive, a convenient pair is formed. Having a locomotive facing each direction allows for quick turnarounds, as the backward locomotive can quickly serve as the leading locomotive when necessary. The efficacy of this pairing is what makes it a standard practice in the rail industry today.

Where did surnames originate?

Surely we can all name at least one mononym, or an individual addressed by a single name. Many Greek philosophers, like Socrates, Plato, and Aristotle, are only addressed by one name. Similarly, historical figures like Pocahontas, Montezuma, Stalin, and Michelangelo are only addressed by one name. Not all mononyms only have one name, though. In fact, the majority of mononyms have first, middle, and last names; the adopted single name can result from a number of different factors, like fame, a pseudonym, or simplicity.

The origin of surnames is usually attributed to China and the Roman Empire. Before the public at large used surnames, the privilege was reserved for the aristocracy in large empires. In as early as 3000 B.C., most of the public in China used surnames. Around 3000 years later, the Roman empire followed suit. As populations grew around the world and the need for easier identification rose, the use of surnames increased exponentially. Countries in the Western world were next in adopting surnames. It is estimated that the turn of the 16th century marked the time where the heavy majority of people had surnames at birth.

Why don't deep-sea fish get crushed by pressure?

Unlike humans, many species of fish are able to survive the pressure of the deep ocean. Deep-sea fish can survive this pressure because there is a negligible pressure difference between their insides and the water. In other words, they don't have any spaces full of air to be crushed. A gas-filled organ often found in fish, a swim bladder, is missing in deep-sea fish. Without this bladder, deep-sea fish do not have to worry about being crushed.

Why do our tongues stick to metal in the winter?

This question addresses a dare—or to remain true to the movie, a "triple dog dare"—popularized in A Christmas Story: to stick your tongue to a pole in the winter. A tongue can stick to metal if the metal is below the freezing point of water, 32° Fahrenheit. This phenomenon occurs because the water on a tongue freezes when it touches a sub-32°F metal. Of course, if a metal is very cold, then a tongue will freeze to it more quickly.

The property which allows this rapid freezing to occur is thermal conductivity, or the ability of a material to conduct heat. Metal has considerably high thermal conductivity which means, in the case of the tongue-to-metal dare, it is able to absorb the heat of the tongue at a faster rate than the body is able to supply heat to the tongue. This high thermal conductivity is responsible for quickly cooling the water on a tongue to a temperature where it can freeze. Aside from metals, other materials of high thermal conductivity, like ice, can cause a similar freezing effect. In contrast, materials of low thermal conductivity would not be able to overcome the heat being supplied to the tongue, so the freezing effect would not occur.

Do fish sleep?

Fish do sleep, but not by human standards. Specifically, they enter into a state of rest which serves a similar purpose as sleep. Instead of going unconscious and entering into various stages of sleep like humans, fish usually float in one place or rest on a stable surface (e.g. coral, sea bottom, etc.) and enter an energy-saving, restorative state. In this state, fish will become less aware of their surroundings and their metabolism will slow. Interestingly, research has shown that fish exhibit symptoms of sleep-deprivation if they do not get enough rest.

Is the sea level the same around the world?

Intuition seems to suggest that the ocean should even itself out around the world. Interestingly, this is not the case. The sea is not the same height around the world; rather, local sea levels vary for a number of reasons. These reasons include the presence of ice sheets, changes in prevailing winds, differing ocean currents, the presence of coastal mountain ranges, and more. The global sea level measure is an average of the local sea levels around the world. The National Oceanic and Atmospheric Administration (NOAA) tracks the latest trends in sea levels. These trends are available for viewing via the NOAA website here.

Where do barber poles come from?

Barber poles date back to medieval times when barbers not only performed hair cutting services but tooth extraction and bloodletting as well. In the process of bloodletting, a patient would hold and squeeze a red pole to increase blood circulation (and to hide blood stains). After bloodletting, the patient would receive bandages to heal. The white on the barber pole represents these bandages. In order to advertise their services to the public, barbers would wrap a red bloodletting pole with white bandages and put it outside of their shop.

In some places, like England, legislation dictated that surgeons needed to be distinguished from one-trade barbers, so barbers were required to advertise with blue on their pole while surgeons would use red. Some barber poles in the United States have red, white, and blue colors rather than the traditional red and white. This phenomenon is thought to be an expression of the country's national colors. Alternatively and in conjunction with the bloodletting theme, the blue could represent deoxygenated venous blood while the red represents oxygenated arterial blood. Today, barbers shops around the world continue to place barber poles (although commercialized and plastic) outside of their shops to advertise their services.

What is quicksand and how do we escape it?

Quicksand is not a particular type of sand per se; rather, quicksand is ordinary sand mixed with water. When enough water gets trapped in sand (i.e. suspended and unable to flow), it reduces the friction between sand particles such that the sand can no longer support weight. In the right conditions, this mixture of sand and water forms what we know to be quicksand. Quicksand usually forms when a certain underground source of water rises into a bed of sand.

Escaping quicksand is counterintuitive. The typical reaction of a person who has stepped (or fallen) into quicksand is to panic and struggle to get out. Such thrashing only causes the person to sink faster because, as mentioned before, water is preventing the usual friction between sand particles. There are a few key things a person should do to escape quicksand. First, they must remain calm so as to avoid hastening their sinking. Second, they should increase their surface area by spreading their arms and legs out. Next, they should lay on their back and stay still, allowing them to float to the surface. Since humans are less dense than quicksand (the mixture of sand and water), they should float to the surface. If the floating strategy fails, then the the next step is to make slow movements and attempt to climb to the surface.

Where does the phrase "once in a blue moon" come from?

The phrase "once in a blue moon" is used to indicate a rare event. Fittingly, the event of a blue moon is indeed rare...and no, the moon is not actually blue. A "blue" moon refers to the second full moon in a single month. Since a typical lunar cycle lasts about 29.5 days, it is rare for any single month to witness two full moons. The last blue moon took place recently on August 31, 2012.

There is a different, older definition of a blue moon which refers to the third full moon in a season with four full moons. This old definition has slowly atrophied with time as the new definition has popularized.

What's the difference between jam and jelly?

The difference between jam and jelly lies not in their source but in their composition. Jam is made by crushing fruit and is served in that form (with small chunks of crushed fruit). Due to the fact that jam is served as crushed fruit, it is naturally thick enough to spread. Unlike jam, jelly is made from only fruit juice. In order to reach a consistency that is able to be spread, the fruit juice is mixed with a skosh of pectin. Thus, the difference between jam and jelly is simply the presence of crushed fruit.

Why do mosquito bites itch?

When a mosquito bites you (or stabs you with its proboscis, to be proper) it injects saliva that contains enzymes and anticoagulants, which act to speed up its intake of blood. As a response to the saliva, your body will release histamine. Histamine will cause the inflammation of nearby cells which leads to the ensuing itchy, red bump. As we know, this bump will itch, and irritating the bump by itching it will only lead to greater inflammation.

Quick fact: Only female mosquitoes bite humans because they need the nutrients in blood to properly develop their eggs.

What is the difference between a motel and a hotel?

That which distinguishes a motel from a hotel can be found in the word "motel" itself. The word motel is derived from "motor" and "hotel," words that describe its purpose well. Motels are usually located in rural areas or along the edge of cities to accommodate travelers and commercial drivers. With their customer base being what it is, motels rarely take reservations; rather, they encourage an atmosphere where anyone can walk in at anytime and stay the night. Usually, motels are single-story or double-story buildings with rooms opening up to the exterior.

Hotels, on the other hand, are located more densely in urban areas and/or popular tourist areas. Unlike motels, hotels are reservation-oriented and will rarely have walk-in customers. Also, hotels normally have multiple stories and often have amenities that motels lack such as room service, cable television, pools, exercise rooms, restaurants, and business centers, among other things. In terms of customer base, hotels cater to families and groups on long-stays/package deals or simply people that know in advance that they will be spending a few nights away from home and don't mind paying the extra cost of a hotel.

What is the difference between leavened and unleavened bread?

If bread is made without a rising agent it is called unleavened, or flatbread; the ingredients for unleavened bread can be reduced to flour, water, and olive oil.  If a rising agent, like yeast or baking soda, is added to the recipe, the bread will be undergo a leavening, or rising, action, producing leavened bread. Leavened bread is pervasive in Western countries while unleavened bread is fairly uncommon, at least outside of a religious context.

Why do bees die after they sting you?

A common misconception is that all bees die after they sting you. In reality, only honeybees die from stinging. A honeybee has a barbed stinger that is attached to its abdomen as well as some muscle tissue and nerves. If a honeybee were to sting a thin-skinned animal, then the bee would be able to pull its stinger out of the animal with little effort. Conversely, if a honeybee were to sting a thick-skinned animal (like a human), then the bee would not be able to pull its stinger out. With enough effort, however, the honeybee could break free from its stinger, leaving it in the animal's skin. Unfortunately, breaking free comes at a price. Part of the bee's abdomen (along with muscles and nerves) is torn from its body, often causing death.

New university building standard: two doors, one handle

If you are a student or a faculty/staff member at a college, you may have noticed a peculiar detail about new buildings. Many high-traffic buildings, like residence halls, libraries, and academic halls, require double-door entrances. It seems logical to assume that both of the doors would have outside handles so as to minimize any potential traffic buildup. This is not the case. The presence of only one handle is a reaction to the shooting event at Virginia Tech in April 2007. Before the shooter, Seung-Hui Cho, began his attack, he fastened chains around a few pairs of double-door handles and secured them with numerous locks, preventing anyone from escaping. Since this attack, many universities have chosen to put only one outside handle on double-door entrances of new buildings.

How do colored contacts work?

Colored contacts are becoming increasingly popular and are entering the daily wardrobe. These contacts can either be very easy or nearly impossible to recognize. There are various types of colored contacts presently available: opaque contacts act to completely change an eye color; enhancement contacts supplement an already existing eye color; and equinox lenses emphasize the existing color by creating a black outline around the iris. Opaque and enhancement colored contacts work in the same way but have a small difference. Since opaque contacts are meant to change eye color completely, they have a relatively thick amount of the desired color on the contact. Enhancement contacts have a thin layer of the same color as the user's eyes on the contact. The coloring on these contacts is shaped to completely cover a person's iris. In order to make this overlap work, the color contact lenses are personalized, or fit to each person's eyes. Equinox contacts are colored in a way that a person's iris is outlined in black, therefore accenting their natural color. Also of note is the fact that a colored contact has a clear section as large as a pupil so users can see without having tinted, colored vision.

Why do pine trees retain their green color throughout the winter?

Pine trees are able to maintain green leaves, or pines, throughout the winter because of the nature of their leaves. Specifically, pine trees have needle-like leaves that prevent the escape of water through the stomata (slowing transpiration). This retention of water facilitates photosynthesis all year round as water is a necessary resource for conducting photosynthesis. Besides their shape, pine needles are covered with a waxy coating that retains water by slowing its evaporation. The combination of needle-shaped leaves and wax coatings allows pine trees—fittingly called evergreen trees—to persist in their green state throughout the year.

Why are traffic lights red, yellow, and green?

Railroad engineers first used traffic signals in the 1830s to direct trains. The earliest form of this signal system used a clear (standard/white) color to indicate "proceed" and a green color meaning "caution." Due to the fact that clear lamps were used in street lights and households, train conductors would frequently interpret them to mean "go," even if the real traffic signal shined green. Needless to say, this misinterpretation caused problems. On their second attempt, railroad engineers created a traffic signal with the colors red, yellow, and green. They selected a red color to indicate "stop" because they thought it intuitively elicited feelings of danger, perhaps because blood is red. Yellow was chosen to mean "caution" because it is close to red yet still distinguishable from it. Lastly, green was chosen rather haphazardly to indicate "proceed." Most likely, the green color was carried over from the original traffic signal design for simplicity's sake and the fact that it was not pervasive in streetlamps and households.

The first traffic signal to be installed on a road was in London in 1868. This gas-powered lantern had a red light meaning "stop" and a green light meaning "caution." Next came the creation of the electric traffic light, which also only had a red and green light. The yellow "caution" light was not carried over from railroad to road right away; rather, a buzzer on the traffic light would indicate that a signal change was about to occur. In 1920, however, William Potts reintroduced yellow lights in his creation of the first electric, three-color stop light in Detroit, MI. From there, green indicated "proceed," yellow "caution," and red "stop." The electric stoplight spread rapidly throughout the United States and then the world, keeping the same three signature colors.

So what is gluten?

Gluten is a protein found in grains like wheat, rye, and barley. This protein contributes to the property of elasticity in dough. It is estimated that roughly 10% of the U.S. population has some sort of gluten intolerance, which has given rise to the gluten-free diet. Those with gluten sensitivity experience a variety of symptoms like upset stomach, headaches, diarrhea, and fatigue. Many of the symptoms of gluten sensitivity are shared with celiac disease, a similar but different condition. In more severe cases, gluten can lead to schizophrenic and hyperactive behavior.

Is sea salt a healthy alternative to table salt?

Contrary to popular belief, sea salt is not a healthy alternative to table salt. In terms of nutritional value, the two options are essentially equivalent, as they contain the same amount of sodium. There are, however, distinctions between the two additives. Sea salt is obtained by simply evaporating sea water. Usually no formal processing of the sea salt is performed, which can result in it containing a number of minerals. These minerals give sea salt a different flavor than table salt, its processed counterpart. Table salt is obtained by mining salt deposits and is usually processed to remove many of the minerals found in sea salt. The only other notable difference between sea salt and table salt is texture. Sea salt is large (relatively), rough, and rigid whereas table salt is small, refined, and consistent. One good thing about sea salt, though, is the fact that it is all natural.

Why do we only see the tip of an iceberg?

Water is unique in that it is less dense as a solid than a liquid. Ice has a density of 0.9167 g/cm^3 while water has a density of 1.0 g/cm^3. Since ice is only about 10% less dense than water, only 10% of an iceberg appears to be floating while the other 90% is submerged. In order for the ice's buoyancy to balance with the amount of water displaced, only 10% of the iceberg remains above water.

What is the relationship between the United States and Puerto Rico?

Puerto Rico is U.S. territory but not an official state; rather, it is an independent community, or commonwealth. Puerto Ricans are considered U.S. citizens and have all of the same rights involved with that status, except the ability to vote in presidential elections. Puerto Rico is self-governed with the governor being the highest authority. Also, Puerto Rico has a Senate, House of Representatives, and Constitution. Two interesting facts about the Puerto Rico-U.S. relationship are that Puerto Rico has its own flag and it uses U.S. dollars as currency. Additionally, in the Olympics, Puerto Rico competes independently from the United States. Lastly, the populace of Puerto Rico is divided on the issue of statehood (whether it should apply to be an official U.S. state). It is not likely, however, that statehood will become a reality in the near future even if its apologists garnered the necessary support.

Why do birds fly in a V?

When in groups, birds often fly in a V formation. This formation is a likely that they are traveling a far distance. In order to reduce the amount of energy spent on their journey, birds fly in a V shape. In the V formation, each bird flies a little behind and above the bird in front of it. This way, each bird (except the front one) experiences less wind resistance and therefore doesn't have to exert as much effort flying. Each bird takes a turn leading the V formation to allow the others to rest. Another advantage of the V formation is that the birds in the back can keep an eye on the other birds to make sure no bird gets lost or falls behind.

Topping off your gas tank: Habit of harm?

It may be a habit of yours to top off your gas tank in order to round the price to the nearest dollar. Although this practice seems benign, it actually harms your car, the gas pump, and the environment. Topping off your gas tank can result in your car's vapor collection system being ruined, causing your car to idle sporadically and possibly stop working. The excess gas can evaporate into the car's vapor collection system which, in addition to the aforementioned problems, can lead to higher gas emissions. Adding extra gas to your tank can damage the gas pump by causing the pump's vapor recovery system to fail; this failure could potentially cause the pump to stop working entirely. One surprising fact is that much of the excess gas that you think is going into your fuel tank is actually being absorbed into the pump's storage system. In other words, you are paying for gas that you don't get and filling the pump's hose for the next person in line (a nice, silent boon).  In terms of environmental harm, topping off your gas tank can increase your car's emissions as well as cause gas to spill, wasting gas (and your money) and polluting the air.

Where does "love" come from in tennis?

Tennis originated from a 12th century court-based game called paume. The scoring in tennis, particularly the no-point term "love," is peculiar. One leading theory about the origin of "love" is that it is a spin off of, or perhaps English mispronunciation of, the French word l'oeuf, meaning egg. The shape of an egg resembles a zero, which a suitable way to represent no score. The only other leading theory about the origin of "love" is that the people who play tennis solely for the "love of the game" play it for nothing. In other words, even if people tirelessly play tennis and cannot seem to earn a point, at least they have love (for the game, that is).

Why are fire hydrants different colors?

Fire hydrants are painted different colors to reflect the amount of water they can expel. Blue hydrants can expel the most at 1500+ gallons per minute (gpm). Green hydrants expel 1000-1500 gpm, orange/yellow hydrants 500-1000 gpm, and red hydrants <500 gpm. In certain cities, the knobs on each hydrant are painted different colors to indicate the pressure of each hydrant. Green knobs indicate a pressure of over 120 pounds per square inch (psi), orange knobs 50-120 psi, and red knobs <50 psi. When firefighters arrive at a scene, they need to be able to quickly identify what is needed to suppress the fire. They need to know how much water is readily available so they can tap other resources if necessary. The color-coated hydrants/knobs assist firefighters in their initial assessment of available resources.

Why is the QWERTY keyboard arranged as it is?

The QWERTY layout remains the most popular keyboard layout today. It was originally designed by Christopher Sholes, who put it on the Remington Number 1 typewriter, the first commercial typewriter produced by Remington & Sons back in 1873. When Sholes designed the QWERTY layout, he kept in mind the key mechanism of the typewriter; when a key was pressed, a bar connected to the key would depress onto an ink-holding adhesive, imprinting the letter shape onto the paper behind. Occasionally, when two keys were pressed in rapid succession, the bars connected to the keys would hit each other and cause a tangle. To avoid such setbacks, Sholes figured out which letters were used most commonly together (like th, ie, and ou) and placed them away from each other on the keyboard.

Aside from separating the commonly paired letters, Sholes went about the keyboard design in a haphazard way. The final layout turned out to be the QWERTY layout we know today. Various other keyboard layouts were designed in an attempt to maximize typing speed, like the Dvorak and AZERTY systems, but these proved roughly equivalent in speed to the QWERTY system. The old adage "if it's not broken, don't fix it" explains why the QWERTY layout persists today. The QWERTY system is so pervasive that it is likely to remain the standard keyboard layout for many years to come.

How to identify poison ivy

A general rule of thumb for avoiding poison ivy is "leaves of three, let it be." If you follow this mantra, chances are you will indeed avoid poison ivy because in all seasons it comes in leaves of three. Since summer encourages visits to forests/parks (areas harboring poison ivy), it is important to be able to identify poison ivy to avoid having your week ruined. Poison ivy has notched leaves, not uniformly ridged leaves, and its leaf formations are rarely symmetrical. Also, poison ivy leaves are usually wide at the base of the leaf.

When poison ivy begins to grow, its leaves are particularly shiny. As the plant ages, the leaves lose their shine and become dull. Another tip for avoiding poison ivy is to pay special attention to the edge of forests, fields, and paved surfaces because poison ivy commonly grows on such boundaries. Above is a picture of poison ivy in the summer. See if you can identify the aforementioned characteristics.

Above is how poison ivy looks in the autumn. Like many leaves in autumn, poison ivy leaves can be colorful, so don't be fooled by the appealing red and yellow leaves.

Pictured above is poison ivy in the spring. Although poison ivy remains primarily green in the spring, some leaves can be red.

Venus flytrap: the staple carnivorous plant

Many people are not aware that hundreds of species of carnivorous plants exist. In order for a plant to be considered carnivorous, it must be able to lure, capture, kill, and digest prey. The most famous carnivorous plant is the venus flytrap. The venus flytrap has a diet comprising arachnids, insects, caterpillars, and slugs. The venus flytrap attracts its prey with a sweet nectar in its trap mechanism. On the leaves forming the trap mechanism there are many small hairs that serve as triggers for the trap. In order for the trap to go off, more than one hair needs to be touched in succession; this double-tap requirement allows the plant to distinguish between prey and other debris. Once the trap closes, the prey is sealed very tightly and various acidic, digestive juices are secreted. The prey is digested fairly quickly and the plant absorbs the nutrients within. This four step process—attract, capture, kill, and digest—is standard for all carnivorous plants.

How do tornadoes form?

When there is warm and moist air in the lower atmosphere and cold air in the upper atmosphere, the conditions are ideal for a tornado to form. The next necessary step is some type of catalyst, usually a strong wind gust or change in wind direction, that causes the warm and cold air to mix. The catalyst causes warm air to rise, creating an updraft and facilitating early cloud rotation (usually vertical rotation). As warm air continues to ascend into thunderstorm clouds and wind gusts occur, a strong vortex will form and eventually touch down to form a tornado.

How do one-way mirrors work?

One-way mirrors are most commonly used in interrogation rooms, teleprompters, and security monitoring (usually to hide a camera or make us perceive a camera is present). The premise of one-way mirrors is to allow a person on one side to see through it while a person on the other side sees only a reflection. Unfortunately, there is no such thing as a one-way mirror per se, but the illusion works with the help of lighting. To create this illusion, a piece of glass is coated with a very thin layer of reflective metal (e.g. aluminum); this surface is often called half-silvered. A half-silvered surface will not reflect nearly as much light as a thickly coated surface, but it still reflects around half of the light that hits it. This way, if one side of the half-silvered surface is brightly lit, then enough light will reflect off of it to make one's reflection appear on that side. The other side of the glass is often kept very dark, allowing a viewer to see through to the lit side.

To better understand how light creates a one-way illusion, try this test. Look out a window when it is sunny outside and dark inside. Notice how easily you can see through the glass and observe what is happening outside. Now, look out the same window at night when it is dark outside and your house/office is brightly lit. Do you see your reflection? Can you still see what is going on outside? If you can grasp the importance of lighting using just plain glass, then you can easily understand the difference that a thin reflective layer (i.e. half-silvered) makes in creating the one-way mirror illusion.

Where does the phrase "flying colors" come from?

It is quite common to hear that somebody has passed a test or won a race "with flying colors." This phrase is normally used when referring to victories or accomplishments, and it is used as a replacement for adverbs such as "easily" and "comfortably." This phrase originated in the 17th century when naval fleets returned home after a victory flying their country's flag. Citizens would see their colorful flag and know the mission was successful. Thus, the flag became associated with not only victory, but with easy victory. Today, the phrase "flying colors" persists in a number of different languages.

Why are barns red?

Hundreds of years ago, European farmers used a mixture of linseed oil, milk, and lime to paint the wood on their barns. The red on barns came from the addition of rust (ferrous oxide) to the paint mixture. When the mixture dried, it resulted in a dampened red color. Farmers decided to add rust to their mixture because it would prevent the spread of and kill fungi and mosses that would grow on their barn and decay the wood. Some people theorize that the red on barns came from including a slaughtered animal's blood in the paint mixture. When European farmers settled in America, they brought with them the soon-to-be tradition of the red barn. Although there are countless colors of paint to choose from at an affordable price today, farmers still have a proclivity to paint their barns red, perhaps for the sake of tradition or because it has become somewhat of a farming trademark.

Why do pennies and nickels have smooth edges?

Pennies and nickels have smooth edges whereas dimes, quarters, half dollars, and dollar coins have rough edges. When dimes, quarters, etc. were first minted, they were composed mostly of silver and copper. The value of these materials led many underhanded people to shave off the edges of the coins in hopes of selling the collected shavings. The coins were being devalued, yet they were still being accepted at full value in commercial businesses and banks that were not aware of the shaving. In 1965, however, dimes, quarters, etc. were minted with rough edges to prevent shaving. If a bank noticed that the rough edge of a quarter, for example, was shaved, it would refuse to accept the quarter. From the beginning of their production, pennies and nickels were composed of less valuable metals such as zinc, aluminum, and copper, so shaving them carried little incentive. Today, despite the fact that dimes, quarters, etc. are not made with real silver, the characteristic rough edges have still been kept in their production.

Origin and purpose of the AMBER Alert

The AMBER Alert was named after Amber Hagerman, the soon-to-be-ten year old girl who was kidnapped and murdered in Arlington, TX in 1996. Fort Worth radio broadcasters and the local police department developed an early warning system to apprise the public of child abductions. Communities around the nation followed suit and developed their own warning systems. Today, AMBER has been adopted as an acronym for America's Missing: Broadcast Emergency Response. AMBER Alerts are distributed through a number of different outlets, including cells phones (via SMS), email, televisions, public billboards, and radio. The statistics on kidnappings that lead to murders are troubling, and they prove that every second matters in abductions. AMBER Alerts were developed in response to this realization, and they help to prevent as many "unhappy endings" as possible.

How to read the moon phase

Reading the moon phase is very simple. The 29.5-day moon cycle starts with a new moon, when no moon is visible to us because it is located between the earth and the sun. Next begins the waxing phase, when the moon transitions from a new moon to a full moon. The waxing phase is called "waxing" because the moon appears to become larger. As the moon reveals itself in the shape of a crescent, it is called a waxing crescent. The next phase is often referred to as a half moon, but the correct term is first quarter moon, when only the right half of the moon is visible. The next phase is called a waxing gibbous, pictured above. Next comes the enemy of the superstitious, the full moon. When the moon is full, the waxing phase ends and the waning phase begins. The waning phase occurs when the moon appears to be disappearing. The waning phases are flipped versions of the waxing phases: the waning gibbous, third quarter (another "half moon," this time only the left side of the moon is visible), waning crescent, and lastly the new moon. With the appearance (or rather disappearance) of the new moon, the moon cycle is complete.

Are gold medals really gold?

You may not be surprised to learn that gold medals are not 100% gold, at least not anymore. When the Olympic Games first began, gold medals were composed of 100% gold. Unfortunately for modern Olympic athletes, that practice ended more than 100 years ago. Today, certain design and composition elements are chosen at the discretion of the Olympic organizing committee of the host city, but there remain certain standards that must be upheld no matter the venue. All gold medals must contain at least 6 grams of gold, gold and silver medals must be at least 92.5% silver, and all medals must have a minimum thickness of 3mm and minimum diameter of 60mm.

Post-workout protein: the key to a quick recovery

You have probably been told to eat protein-rich foods after a tough workout. Eating protein is an essential part of recovering from a workout because it provides your body with the necessary materials to repair the damage done while exercising. Working out causes your muscle fibers to tear, leaving them without amino acids. If you supply your body with protein (composed of amino acids) right after a workout, the torn muscles will be repaired more quickly. When muscle fibers are torn, they are repaired to a stronger state, so if you are looking to build muscle be sure to always eat protein-rich foods after your workouts.

How is cotton candy made?

We all love cotton candy—that fluffy, sugary, melt-in-your-mouth treat found at the likes of Chuck E Cheese's and summer fairs. Making cotton candy is an interesting and simple process that turns ordinary granulated sugar into the fluffy state that we know and love. First, a heating device with small holes on the sides is placed in a bowl and attached to a spinning mechanism. Then, flavored sugar (often known as cotton candy sugar) is placed in the heating device. The sugar heats to 375°F and melts into a liquid state. After the sugar is melts, the heating device spins, causing the liquid sugar to exit through the small side holes, cool almost instantly, and transform into solid threads. Lastly, the threads are collected (usually on a cone) and the process is complete.

Why do athletes yawn before their performances?

If you are watching the 2012 London Olympics and paying attention to the athletes before they perform, you may notice that many of them yawn right before the start of their event. This phenomenon is common and has been researched extensively. Although yawning is not fully understood, research indicates that it is a thermoregulatory behavior. Specifically, yawning acts as a cooling mechanism when the brain gets too hot. When we yawn, a rush of cool air is taken in; this air is believed to cool the brain through the mouth's palate. The brain is often described as a complex computer system, and like the non-organic computers we have today, it works most efficiently at a cool temperature. By cooling the brain, yawning is believed to revitalize the senses and increase concentration. What better time than right before an athletic performance to increase one's focus and alertness? Most athletes yawn naturally before their events, but others induce their yawns for the seeming benefits. Yawning can be induced by seeing others yawn, reading about yawning, or even thinking about yawning. Have you yawned yet?

How do farm irrigation systems work?

No trip to the Midwest is complete without seeing a lot of farm fields. In those fields, of course, are irrigation systems. Although these irrigation systems appear to be fairly simple, they are actually quite advanced. One of the most pervasive irrigation systems is the center pivot system. At the pivot of this system is a source of water, which spreads to each individual segment. Rotation around the center pivot point is granted by individual electric motors found on each set of wheels. The outermost set of wheels controls the speed of revolution of the whole system. Typically, the outer wheels move at a faster rate than the inner wheels so as to maintain segment alignment, and various angle sensors report to a computer to coordinate wheel speeds. The individual nozzles found on each segment vary in size (and therefore water emission) in order to achieve application uniformity—the closer to the center, the smaller the nozzle size.

The launch of this blog and the 2012 London Olympics

Today, July 27, 2012, celebrates the beginning of the 2012 Summer Olympics in London and the launch of this blog, DiurnaLearn. The purpose of this blog is to promote learning every day, which can be gleaned from its title. Learning something new every day can enrich our lives and can change the way we see the world; it calls our attention to the small, often-overlooked details all around us.

Since the 2012 Olympics is upon us, I think it is fitting to learn about the five interlocking rings that  serve as the official symbol of the Olympics. The now-ubiquitous symbol was designed in 1912 by the founder of the modern Olympics, Pierre de Coubertin. The five rings symbolize the five continents competing in the Olympics, namely the Americas (North & South), Europe, Asia, Africa, and Oceania. The colors of the rings embrace the colors found on the national flags of all participating countries. Although there may be a color on a country's flag not found on the rings, the rings will contain at least one color on each country's flag. The fact that the rings are interlocked represents the valuing of sportsmanship and the coming together of all countries for healthy competition.